# SPDX-License-Identifier: Apache-2.0

# dtc is an optional dependency
find_program(DTC dtc)

if(DTC)
  # Parse the 'dtc --version' output to find the installed version.
  set(MIN_DTC_VERSION 1.4.6)
  execute_process(
    COMMAND
    ${DTC} --version
    OUTPUT_VARIABLE dtc_version_output
    ERROR_VARIABLE  dtc_error_output
    RESULT_VARIABLE dtc_status
  )

  if(${dtc_status} EQUAL 0)
    string(REGEX MATCH "Version: DTC ([0-9]+[.][0-9]+[.][0-9]+).*" out_var ${dtc_version_output})

    # Since it is optional, an outdated version is not an error. If an
    # outdated version is discovered, print a warning and proceed as if
    # DTC were not installed.
    if(${CMAKE_MATCH_1} VERSION_GREATER ${MIN_DTC_VERSION})
      message(STATUS "Found dtc: ${DTC} (found suitable version \"${CMAKE_MATCH_1}\", minimum required is \"${MIN_DTC_VERSION}\")")
    else()
      message(WARNING "Could NOT find dtc: Found unsuitable version \"${CMAKE_MATCH_1}\", but required is at least \"${MIN_DTC_VERSION}\" (found ${DTC}). Optional devicetree error checking with dtc will not be performed.")
      set(DTC DTC-NOTFOUND)
    endif()
  else()
    message(WARNING "Could NOT find working dtc: Found dtc (${DTC}), but failed to load with:\n ${dtc_error_output}")
    set(DTC DTC-NOTFOUND)
  endif()
endif()

find_program(SHELL sh REQUIRED)

find_program(GREP grep REQUIRED)

find_program(BC bc REQUIRED)
